Measuring nonlinear reflectance of laser radiation with a wavelength of 2940 nm from silica glass – water and silica glass – ethanol interfaces

We have measured the reflectance of an Er³⁺ : YAG laser pulse from silica glass – water and silica glass – ethanol interfaces at high (0.9 J cm^-2) and low (5 mJ cm^-2) energy densities of incident radiation. The nonlinearity of reflectance dynamics is found for high-power radiation during the laser pulse action.